Question

I have a model Store with attributes user_id, product_id and token_string.

In the form I collect values for user_id and product_id but not token_string because it is going to be generated after user_id and product_id are saved.
So in the create action the @store is saved normally with only two attributes values and nil token_string.

But right after @store is saved i want to generate a random token_string(doesn’t matter how) and save it to the database on the same row as product_id and user_id where there is nil(i am not sure if update_attribute would do).But the biggest challenge is there is a number from a variable i have to multiply to token generation.

So lets say the number is 2
That means i would generate two token_strings and both have to be saved to the same user_id and product_id.How do i go around this?

Thank you in advance

    def create
      @quantity=2
      @store=Store.new(params[:store])

      if @store.save
         @quantity.times{ generate token string}
         #Then save both generated tokens to the same user_id and product_id
        redirect_to :controller=>"products",:action=>"index"
      else
        redirect_to :action=>"new"
      end
    end

Answer 1

if you need to save token_string in the same record

class Store < ActiveRecord::Base

  before_save :token_generate

  private

  def token_generate
    self.token_string = Digest::SHA1.hexdigest(user_id + token_id + Time.now)
  end

end

but if you need to duplicate the @store with the same user_id and product_id that method can be helpful

# model
class Store < ActiveRecord::Base
  def duplicate_with_token!(quantity)
    1.upto(quantity) do
      obj = self.clone
      obj.token_string = Digest::SHA1.hexdigest(user_id + token_id + Time.now)
      obj.save
    end
  end
end

# controller
class StoresController < ApplicationController
  def create
    @store=Store.new(params[:store])
    if @store.save
      @store.duplicate_with_token!(2)
      #Then save both generated tokens to the same user_id and product_id
      redirect_to "products#index"
    else
      redirect_to :new
    end
  end
end